EAGER SitS: Emergent Properties during Soil Formation

土壤维持着人类。这些地球物质是由水、空气、死生物体和活生物体与地球表面的岩石物质相互作用而形成的。土壤的形成需要数千至数百万年的时间，但随着人类时间的推移，土壤可能会因侵蚀而流失。在这项拟议的工作中，创新的传感器和技术将用于测量和了解细菌催化铁和氧如何在土壤中相互作用，从而影响水在地下流动的路径。这项工作将重点关注宾夕法尼亚州国家科学基金会资助的一个关键区域天文台的土壤形成，该天文台正在付出巨大努力来了解这些过程。新的科学知识将得到发展，涉及微生物如何改变岩石的化学性质，并在岩石变成土壤时将其分解，以及这与地下水流的关系。与此同时，新技术将提供有关土壤如何形成的社会相关性的新知识，并将通过与当地博物馆的互动向参观天文台的许多其他教职人员、学生和同事以及公众展示。此外，该天文台还是美国国家科学基金会资助的年度地球物理学现场课程的举办地，其中将向来自代表性不足的群体和社区学院的年度本科生教授这两种技术。通过使用新颖部署的高风险实验，将探索生物地球化学反应与侧向水流区域的关系。将在长达数月至一年的部署中研究两种技术：第一种技术将测量微生物活动（计时电流分析法），第二种技术将测量水引起的岩石材料体积变化的影响（延时地震监测）。这两种技术仍处于起步阶段，因为它们依赖于新的传感器技术和最先进的解释。在已经进行了许多其他测量的地方一起部署这些技术将保证最大的成功可能性。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

Soils sustain humankind. These earth materials form as water, air, and dead and living organisms interact with rock material at Earth's surface. Soils form over thousands to millions of years and yet soil can be lost to erosion over human time frames. In this proposed work, innovative sensors and techniques will be used to measure and understand how iron and oxygen are catalyzed by bacteria to interact in soils, affecting the pathways where water flows in the subsurface. The work will focus on soil formation at an NSF-funded observatory in Pennsylvania - a Critical Zone Observatory - where a large effort is ongoing to understand such processes. New scientific knowledge will be developed about how micro-organisms change the chemistry of rock and break it open as it turns into soil, and how this relates to subsurface water flow. At the same time, the new techniques will provide new knowledge of societal relevance about how soil forms, and will also be shown to many other faculty members, students, and colleagues that visit the observatory, as well as members of the public through interactions with a local museum. In addition, the observatory is the site of an annual NSF-funded Geophysics field course where the two techniques to be deployed will be taught to an annual cohort of undergraduate students drawn from under-represented groups and community colleges. With high-risk experiments using novel deployments, biogeochemical reactions will be explored with respect to how they relate to zones of lateral water flow. Two techniques will be investigated over month- to year-long deployments: the first will measure microbial activity (chronoamperometry) and the second will measure the effects of water-induced changes in volume of rock materials (time-lapse seismic monitoring). Both techniques are still in their infancy because they depend on new sensor technologies and state-of-the-art interpretations. The deployment of these techniques together in a location where many other measurements have already been made will guarantee the highest likelihood of success.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.